Sfdwhf

When I add a PPA and I want to install some of its content, it is quite annoying to re-update all my apt list using apt-get update.

Is it instead possible to only sync the content of a given repository?

yes, apt-get can do that, and can do it in a nice way.

1. 
   

   Append following to ~/.bash_funcs

   
   
   

   update-repo() {
   
       for source in "$@"; do
   
           sudo apt-get update -o Dir::Etc::sourcelist="sources.list.d/${source}" 
   
           -o Dir::Etc::sourceparts="-" -o APT::Get::List-Cleanup="0"    
   
       done
   
   }
   
   

   
   


2. 
   

   Append following to ~/.bashrc

   
   
   

   if [ -f $HOME/.bash_funcs ]; then
   
   .  $HOME/.bash_funcs
   
   fi
   
   

   
   


3. 
   

   Append following to ~/.bash_completion

   
   
   

   # Debian user-defined completion                             -*- shell-script -*-
   
   
   
   _ppa_lists(){
   
       local cur
   
       _init_completion || return
   
   
   
       COMPREPLY=( $( find /etc/apt/sources.list.d/ -name "*$cur*.list" 
   
   -exec basename {} ; 2> /dev/null ) )
   
       return 0
   
   } &&
   
   complete -F _ppa_lists update-repo
   
   

   
   


4. 
   

   Then source the files

   
   
   

   . ~/.bashrc
   
   . ~/.bash_completion
   
   

   
   


5. 
   

   Done and start to fire it

   
   
   

   update-repo <tab> <tab>
   
   

   
   

You can update a single ppa repository without having to update whole apt source, with implement of bash-completion.

If the repository is configured in a specific file in the directory /etc/apt/sources.list.d/, say myrepo.list, you can update that single repository with the command:

sudo apt-get update -o Dir::Etc::sourcelist="sources.list.d/myrepo.list" 

    -o Dir::Etc::sourceparts="-" -o APT::Get::List-Cleanup="0"

Nevertheless this is not very convenient.

This can be simplified defining a bash function

update_repo() {

    sudo apt-get update -o Dir::Etc::sourcelist="sources.list.d/$1.list" 

        -o Dir::Etc::sourceparts="-" -o APT::Get::List-Cleanup="0"

}

so that you can simply run

update_repo myrepo

Y PPA Manager comes with a command line tool called update-ppa that lets you update a single PPA.

For example:

sudo update-ppa ppa:nilarimogard/webupd8

Also, when adding a PPA through Y PPA Manager, the PPA source is automatically updated (only for that PPA). In a future version, there's going to be a GUI to manually update single PPAs as well.

More information about Y PPA Manager, HERE.

To update a specific repository, use -o, e.g.:

apt-get update -o Dir::Etc::sourcelist=/path/to/repo.list

Here is a one-liner updating only recently added apt repository

find /etc/apt/sources.list.d -type f -name '*.list' -exec sudo apt-get update -o Dir::Etc::sourcelist="{}" ';'

It's much quicker than updating all repositories, especially during VM provisioning after adding new.